Models frequently confuse the search and replace fields in the
edit_files tool (CODAGT-312). Rename the model-facing JSON fields
to old_text/new_text so the intent is unambiguous.
Backend: custom UnmarshalJSON on editFileEdit falls back to
deprecated search/replace when old_text/new_text are empty. The
workspace agent API is unchanged; toSDKFiles maps old_text/new_text
back to search/replace for agent/agentfiles.
Frontend: normalizeEdit in parseEditFilesArgs accepts both
old_text/new_text and search/replace, normalizing to the internal
{ search, replace } representation so streaming diff rendering
works with either field naming convention.
Mathias Fredriksson
32ed9f1f39